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The group 7 elements - chlorine, bromine and iodine

You will be assessed on your ability to

2.9 recall the colours and physical states of the elements at room temperature
2.10 make predictions about the properties of other halogens in this group
2.11 understand the difference between hydrogen chloride gas and hydrochloric acid
2.12 explain,in terms of dissociation, why hydrogen chloride is acidic in water but not in methylbenzene
2.13 recall the relative reactivities of the elements in Group 7
2.14 describe experiments to show that a more reactive halogen will displace a less reactive halogen from a solution of one of its salts
2.15 understand these displacement reactions as redox reactions

Section notes



Investigations


Halogens reacting with iron

Resources

Textbook
page 105 - 109

Worksheets


Animations

Watch the animation below which shows displacement reactions of halogens.
displacement simulation

When a colour change occurs a reaction takes place because the halogen is displacing a halide from its compound
1. Design your own results table and record your observations i.e. colour changes.
2. For each of the displacement reactions write a word equation, a balanced symbol equation and an ionic equation.
3. Which halogen is the most reactive?

video clip of a displacement

Power point